C # Programming Skills

To obtain version information for a file:

FileVersionInfo myFileVersionInfo1 = FileVersionInfo.GetVersionInfo("D:\\TEST.DLL");
textBox1.Text="版本号: " + myFileVersionInfo1.FileVersion;

To change file properties and delete read-only files:

The following example wants to copy the E:\test.txt file to D:\tmp\test.txt, but D:\tmp\test.txt already exists.

//File.Copy(sourceFile,destinationFile,true); 用来拷贝文件
//当destinationFile已经存在时，无法将文件file1拷贝到目标文件，
//因此先删除destination文件，File.Delete()方法不能删除只读文件，
//因此，如果文件属性为只读(Attributes属性中会包含有"ReadOnly")，
//先把文件属性重置为Normal,然后再删除:
string file1="E:\\test.txt";
string destinationFile="d:\\tmp\\test.txt";
if(File.Exists(destinationFile))
{
　FileInfo fi=new FileInfo(destinationFile);
　if(fi.Attributes.ToString().IndexOf("ReadOnly")!=-1)
　　fi.Attributes=FileAttributes.Normal;
　　File.Delete(destinationFile);
}
File.Copy(file1,destinationFile,true);

The format of strings in C # and the method of converting them into numeric values

Converts a string to a number, such as "1234" to the number 1234:

string str="1234";
int i=Convert.ToInt32(str);

Format the string, add a specific character to the end of the string less than 30, complement n characters, and use the PadRight (Int,char) method of the String class:

String str="1234";
str=str.PadRight(30,' ') //向长度小于30的字符串末尾添加空格，补足30个字符

Read and write files by line

To determine if a file exists: File.exists (string FilePath)

Determine if the directory exists: directory. Exists ("D:\\lastestversion")

To read a file by row:

int fileCount=0;
// Open the file just specified such that no one else can use it.
StreamReader sr = new StreamReader(textBox1.Text.Trim());
while(sr.Peek() > -1)//StreamReader.Peek()返回下一个可用字符，但不使用它
{
　listBox1.Items.Add(sr.ReadLine());
　fileCount++;
}
sr.Close();

To write a file by line:

StreamWriter sw = new StreamWriter("D:\\result.txt");
for(int i=0;i<10;i++)
{
　sw.WriteLine("这是第"+i.ToString()+"行数据");
}